-When I started originally my biggest issue was Stone, and its still an overhanging issue, I have too much of it and usually of colors I hate. Letting us designate at a workshop which TYPE of stone to use would go MILES towards making the game more accessible (IE: I only want Brown Tables, I set Mason Workshop to Mudstone, BAM!, I want to consume all of my Microcline, I just simply set my Crafts shop to it and bam!)
You can use DFHack to specify material types in jobs, particularly for stone.
Does the new "give to workshop" for stockpiles not also address this?
It does for me; a few minutes of setup work (literally, just a couple minutes with the wiki's
Page on Stone (which sorts them by color in a table at the bottom), then use the "Give to Workshop" function on a custom stockpile. I have all grey tables and chairs in my dining room, white stone items in my barracks, and so on. I have a junk stone stockpile set to take all the stone that doesn't fit my preferred colors, and it's set to give to my mechanics and crafts shops to chew through unwanted stone as crafts, mugs, pots, and mechanisms.
It is as simple as asking permission from the tileset makers to send them in. They're already incorporated into unofficial releases.
Actually, as Bulwersator pointed out, it's as "simple" as giving an early release of the new version to a graphics pack creator and waiting for them (on a volunteer basis) to completely update for the new version, then cross-referencing it to make sure there are no glitches (since it would become a part of the "official" game, ToadyOne would have a responsibility to ensure it works as intended before it can be released). This of course doesn't address the issue of how to pick which graphics pack to use (even if you narrow it to the most popular, it's neck and neck between three or four).
For me, it's that the game is unfinished. I hate the idea of having to restart a fortress when a new version comes out, even though it's been good recently about backwards-compatibility.
This one actually hurts a lot; Toady has been GREAT about avoiding save-breaking changes recently, but it is frustrating even when there aren't save breaks. I remember when the new livestock system was implemented (can't remember the version, but I believe it introduced beekeeping and eggs), I had to gen a new world to use those features and new jobs, even though it wasn't required to use my old save (I just wouldn't have eggs or bees).
I find myself waiting until a round of bugfixing is completely over before genning a world, mainly in the hopes that Toady WILL take months or more to release another content update, so I don't feel like I'm abandoning a fort just after it got started to enjoy the latest content. There's really nothing that can be done about this, sadly. The game isn't done, the new content is pretty much always exciting, and the alternative is to wait two decades or so until 1.0 is released before downloading an update.